1. Field of the Invention
This invention relates in general to scissors jacks and, in particular, to novel hollow trunnion designs.
2. Description of Related Art
For jacks such as scissor jacks, solid trunnions have been used which are produced by either a turning operation or by cold heading. When produced by turning operations, metal scrap occurs. When trunnions are formed by the cold heading process, more costly tooling than the turning operation is required.
See also the following U.S. Pat. Nos. 2,543,904, 4,836,502, 2,920,871, 4,749,169, 4,720,081, 4,583,713, 4,893,785 and 3,679,176.